Index: llvm/trunk/lib/Analysis/IVUsers.cpp =================================================================== --- llvm/trunk/lib/Analysis/IVUsers.cpp +++ llvm/trunk/lib/Analysis/IVUsers.cpp @@ -253,18 +253,8 @@ const SCEV *OriginalISE = ISE; auto NormalizePred = [&](const SCEVAddRecExpr *AR) { - // We only allow affine AddRecs to be normalized, otherwise we would not - // be able to correctly denormalize. - // e.g. {1,+,3,+,2} == {-2,+,1,+,2} + {3,+,2} - // Normalized form: {-2,+,1,+,2} - // Denormalized form: {1,+,3,+,2} - // - // However, denormalization would use a different step expression than - // normalization (see getPostIncExpr), generating the wrong final - // expression: {-2,+,1,+,2} + {1,+,2} => {-1,+,3,+,2} auto *L = AR->getLoop(); - bool Result = - AR->isAffine() && IVUseShouldUsePostIncValue(User, I, L, DT); + bool Result = IVUseShouldUsePostIncValue(User, I, L, DT); if (Result) NewUse.PostIncLoops.insert(L); return Result; Index: llvm/trunk/test/Analysis/IVUsers/quadradic-exit-value.ll =================================================================== --- llvm/trunk/test/Analysis/IVUsers/quadradic-exit-value.ll +++ llvm/trunk/test/Analysis/IVUsers/quadradic-exit-value.ll @@ -36,7 +36,7 @@ ; sure they aren't marked as post-inc users. ; ; CHECK-LABEL: IV Users for loop %test2.loop -; CHECK-NO-LCSSA: %sext.us = {0,+,(16777216 + (-16777216 * %sub.us)),+,33554432}<%test2.loop> in %f = ashr i32 %sext.us, 24 +; CHECK-NO-LCSSA: %sext.us = {0,+,(16777216 + (-16777216 * %sub.us)),+,33554432}<%test2.loop> (post-inc with loop %test2.loop) in %f = ashr i32 %sext.us, 24 define i32 @test2() { entry: br label %test2.loop